Nanocrystalline titanium-magnesium alloys through mechanical alloying

Abstract

The solid solubility of magnesium in titanium under equilibrium conditions is reported to be extremely small. Mechanical alloying of a mixture of titanium and magnesium powders resulted in the formation of nanocrystalline (10–15 nm in size) grains of Ti–Mg solid solution. This solid solution has a metastable fcc structure with a = 0.426 nm and contains about 3 wt.% (6 at.%) magnesium in it. It is suggested that the fcc structure has formed as a result of the heavy mechanical deformation of the hep structure introduced during milling. High temperature annealing of the metastable solid solution led to its decomposition forming the equilibrium phases, viz., elemental titanium and magnesium.